Zay starts this episode at the southern end of Lake Tanganyika, the world's largest freshwater lake, boarding the Liemba, said to be the world's oldest surviving passenger ferry. Built in 1913 as the Graf von Goetzen in German East Africa, the 230-foot ship was converted into a warship in WWI, scuttled by its own crew in 1916 to avoid capture, raised from the lake bed in 1924, and returned to passenger service, where it still runs a century later. The two-day voyage north covers over 300 miles, stopping at remote villages before Zay disembarks at Kigoma. From there he switches to a 'lake taxi,' a small open boat packed with more than a hundred villagers, to reach Gombe Stream National Park, trekking into the forest at the journey's end. The film follows the working boats and the people who depend on them rather than staging anything for the camera, with the Liemba's wartime history as its centerpiece.